But in last year’s European election, the Conservatives swept into first place in constituencies across Wales, winning in 17 of the 40 Westminster constituencies, including Alyn and Deeside, Wrexham, Delyn, Clwyd West, Vale of Clwyd, Clwyd South and Montgomeryshire.

Tories pushed Labour into a disastrous second place for the first time since the 1918 General Election.

Labour lost one of its two European seats to emerging UKIP, but argued that its core vote had stayed at home.

First minister Carwyn Jones told the Daily Post in an interview last week: “We do have a job to do in making sure that people want to vote Labour again.”

The YouGov poll also asked voters’ intentions in a referendum over increased law-making powers for the Assembly.

Just under half (49%) would vote Yes, down 2% since November, and 32% No, up 2%. But 20% of voters didn’t know or wouldn’t vote.